The Virology and Mouse Immunogenicity Core will provide reliable, consistent, and quality control tested cell lines and viral vectors to the Project Investigators. This will help to ensure uniformity and reliability of in-vitro and in-vivo studies across the three Projects. The Core will also perform side-by-side immunogenicity studies in mice to compare promising vaccine vectors identified by the three Projects. Side-by-side experiments will be critical to help prioritize the constructs for use in non-human primates studies. Therefore, two major aims are proposed: - We will produce and maintain viral stocks for in-vitro studies and for the immunization of mice and non- human primates for Programs 1, 2 and 3. - We will compare HIV-1-specific humoral and cellular immune responses in mice immunized with vaccine candidates identified as promising by the Program Investigators. Consolidating these tasks into a single Core will reduce redundancy and costs, and increase consistency across Projects. RELEVANCE (See instructions): Consolidating these tasks into a single Core will reduce redundancy and costs, and increase consistency across Projects. In addition, immunogenicity studies in mice are important for the evaluation of vaccines against HIV-1.